Electromagnetic cutting apparatus particularly for use, etc.

ABSTRACT

An electromagnetic cutting apparatus for cutting binding tape sewn to the upper and side edges of shoe upper components at the leading and trailing edges of the components includes an electromagnetically operated plunger with a self-adjusting blade on the bottom end thereof, photoelectric sensors for detecting the leading and trailing edges of the components, and an electronic circuit for rapidly charging a coil surrounding a core on the plunger for driving the plunger and blade downwardly to cut the tape. Condensers in the electronic circuit are normally charged and, in response to signals from the photoelectric sensors, instantaneously discharge into the coil to actuate the plunger, which after cutting the tape is returned to a rest position by a helical spring mounted on the plunger.

United States Patent Baran Oct. 15, 1974 [54] ELECTROMAGNETIC CUTTING 3,436,999 4/l969 Lewis et al 83/902 x Q E PARTICULAR FOR FOREIGN PATENTS 0R APPLICATIONS 566,914 12/1958 Canada 83/577 [75] Inventor: Miroslav Baran, Batawa, Ontario,

Canada Primary ExaminerFrank T. Yost [73] Assignee: Bata Shoe Co., Inc., Belcamp, Md. y 8 m-H01man & Stem 22 Filed: Dec. 22, 1972 I [57] ABSTRACT [21] Appl. No.: 319,923

An electromagnetic cutting apparatus for cutting bmding tape sewn to the upper and side edges of shoe Foreign Application y Data upper components at the leading and trailing edges of Dec. 24, 1971 Canada 131 142 the components includes an electromagnetically operated plunger with a self-adjusting blade on the bottom [52] U.S. Cl 83/364, 83/365, 83/371, end thereof, photoelectric sensors for detecting the 83/577, 83/658, 83/679, 83/902 leading and trailing edges of the components, and an [51] Int. Cl B26d 5/32, B26d 5/34 electronic circuit for rapidly charging a coil surround- [58] Field of Search 83/577, 365, 370, 364, ing a core on the plunger for driving the plunger and 83/371, 289, 356.2, 679, 697, 902, 658 blade downwardly to cut the tape. Condensers in the electronic circuit are normally charged and, in re- [56] References Cited sponse to signals from the photoelectric sensors, in-

UNITED STATES PATENTS stantaneously discharge into the coil to actuate the 2 155 578 4/1939 Anderson 83,577 x plunger, which after cutting the tape is returned to a 2,4831138 9 1949 Helmermzj: 2:11: 1:: 83/902 x rest P0Sition by a helical Spring mm'med the 2,589,347 3/1952 Demarath.... 83/577 x P Platt 83/577 X 5 Claims, 11 Drawing g e Glastra 83/577 PATENIEUUBHBW Y 3.841.185

.srmzu 5 FIG.3

PATEM 0m 1 5m SHEET 3 BF 5 FIG. 4

ELECTROMAGNETIC CUTTING APPARATUS PARTICULARLY FOR USE, ETC.

This invention relates to an electromagnetic cutting apparatus and in particular to an electromagnetic cutting apparatus for use in the shoe making field.

When manufacturing shoe uppers of flexible material, e.g., basketball shoes and the like, it is normal practice to sew a strip of binding tape along the upper and side edges of the quarters and tongues used to form the uppers. Such sewing is effected manually by a plurality of operators using separate sewing machines. The binding tape comes in a continuous strip or'roll and is sewed onto a'plurality of shoe upper components'in sausage-fashion before cutting. In other words, an individual operator normally sews a continuous tape onto a plurality of upper components, which are thus interconnected by the binding tape. The tape is then cut manually to separate each of the upper components from each adjacent component. Such separation is effected manually, i.e., with scissors or by an automatically operated cutting device or chopper.

Obviously the manual cutting of the binding tape to separate the components is a lengthy operation and is to be avoided. Presently available automatic cutting apparatus are pneumatically operated and, while much more efficient than manual cutting means, possess the disadvantage that the cutting of the strip is not always accurate.

A skilled sewing machine operator can sew binding tape onto shoe upper components at almost blinding speed. In order to keep up with the operator, the cutting apparatus must be capable of making cuts in rapid succession. It will be appreciated that, with components interconnected in a sausage-like manner, the tape sponse of the apparatus to the cutting requirements encountered in the 'seriatim sewing of. binding tape to components.

The invention will now be described in greater detail with reference to the accompanying drawings, which illustrate apreferred embodiment of the invention, and wherein:

FIG. 1 is a partly sectioned side view of -a cutting apparatus in accordance with the present invention;

FIG. 2 is an elevation view of the chopper portion of the apparatus of FIG. 1 in the direction of arrow 2 in FIG. 1;

- FIG. 3 is a back elevation'view of the apparatus of FIG. 1;

FIG. 4 is a cross-section taken generally along line 44 of FIG. 3; I

' FIG. 5 is a plan view of the apparatus of FIG. 1;

FIG. 6 is a block diagram of a control circuit for use in the apparatus of FIGS. 1 to 4; and

FIGS. 7 to 11 are schematic graphs of the pulses occurring in the circuit of FIG. 6, the ordinates representing voltages and the abscissae representing time.

With reference to the drawings, the cutting apparatus of the present invention includes a frame 1 mounted on a base plate 3. The frame 1 is connected tothe base plate 3 by bolts 4 and 5, which permit vertical adjustment of the frame 1 on the base plate 3. The upper end 6 of the frame 1 is in the form of a yoke 7 or split ring for slidably supporting an arm 8, which extends ou'twardly fromthe yoke 7 over a flat tablev portion 10 of the frame 1. A pair of bolts 11 interconnect opposing ends 13 of the yoke 7 for securing the arm 8 in any desired position.

must be cut at the trailing edge of one component and almost immediately thereafter at the leading edge of the succeeding component. If the cutting apparatus does not keep pace with the sewing machine operator, cuts are made either at a distance from theleading or trailing edge of the component, or on the component itself. In one case, tape wastage and a second trimming step to remove excess binding are necessary, and, in the other case, the shoe upper component is damaged;

It has been found that existing pneumatic apparatus cannot keep pace with skilled sewing machine operators, because the recovery time of the cutting apparatus is often less than the speed of feed of the components and binding tape.

The object of the present invention is to solve the i above problem by providing a'cutting apparatus for relatively rapidly and accurately cutting a binding tape between a plurality of components fed from a sewing machine. I

- Accordingly, the present invention relates-to a cut- 7 ting apparatus for cutting astrip of material connected to a component andfextending beyond at least one edge thereof, the cutting being performed at said edge, such apparatus including an electromagnetically operated plunger with ablade on the outer end thereof. A sensing device is provided for detecting the location of the edge of the'component, and transmitting a signalto the drive portion of the electromagnetic apparatus, whereby the plunger is actuated to cut the tape at such edge.

The use of electronic components in a cutting apparatus of the type described herein results in a rapid re- A generally cylindrical casing 15 is securely mounted onthe outer end of the arm 8 and forms part of a cutting. device. The casing 15 includes integral top and side walls 16 and 17, respectively, an abottom wall 19. The bottom wall 19 is provided with inwardly and outwardly extending tubular portions 20 and 21, respectively which form a housing for a plunger 23 in the form of a rod. The inner end 25 of the tubular wall portion 20. is bevelled, i.e., frusto-conical in cross-sectional configuration for mating with a frusto-conical recess 26 in the bottom endof a cap 28 provided on the .upper end of the plunger 23 in the casing 15. The inwardly extending tubular wall portion 20 and the cap 28 are sur- 1 rounded in the casing 15 by a coil 30 forming part of an electromagnetic circuit (described hereinafter in greater detail). Thus, thecap 28- on the plunger23 forms amagnetic core for the electromagnetic circuit,

and accordinglyis formed of a suitable magnetic material, e.g., iron. The cap 28 is normally biased upwardly .away from the bottom wall 19 of the casing 15 by a helical spring 32 mounted coaxially on the plunger 23, and

extending between the interior of the cap 28 and an enlarg'ed bore 33in the tubular-wall portion 20.

As shown in FIG. 2, a flat, generally rectangular blade 35is'securely mounted in the recessed lower,

outer end 37 of the plunger 23 by meansof a bolt 38 and nut 40. The inner end 42 of the blade 35 is convex and bevelled, and abuts against a concave notch 44 in the outer'end 37 of the plunger 23. Thus, the blade 35 is self-adjusting, i.e., when the' flat cutting edge 45 strikes a flat surface, the blade 35 can rotate about the axis of the bolt 38 so that the entire cutting edge 45 strikes such flat surface.

For cooperating with the blade 35 in a cutting action, a hard metal insert 46 is provided in the table portion 10 of the frame 1. A V-shaped notch 48 in the insert 46 facilitates proper cutting action, since the vertex of the notch 48 defines the point of cutting; The insert 46 is located in an anvil '50, which is removably mounted on the table portion 10, whereby the anvil 50 and insert 46 can readily be replaced when damaged or otherwise altered by wear.

,A holder in the form of a plate 52 is removably mounted with bolts'54'at the side of the table portion 10 adjacent to the anvil 50 for photoelectric sensors 56 and 57. The sensors 56 and 57 include a pair of photoelectric cells 58 and 59 mounted at spaced apart points in the plate 52, and fibreglass filaments (not shown) extending upwardly to adjacent the top surface of the plate 54 fortransmitting light from a light source 60 to the photoelectric cells. The useof fibre optics in the sensors 56 and 57 renders the sensors much more sensitive to the presence or absence of light from the light source 60.

The operation of the apparatus will now be described with reference to FIGS. to 11. o

While a binding tape 63 (FIG. 5) is being continuously sewn onto an upper component-65 travelling in the direction of arrow 66 through'a sewing machine 68, it is desirable to cut the binding strip at the leading edge 69 and at the trailing edge (not shown) of the-component 65. Since the components 65 are fed very quickly through the sewing machine 68, the time lapse between cuts (particularly between cuts at the trailing edge of one component and the leading edge of the next component) is very small.

The sensors 56 and 57 form parts of a circuit (FIG. 6) including pulse conditioners 71 and 72 for modifying the output signal 74 (FIG. 7) from the sensor 56 to form pulse 75 (FIG. 8). The pulse 75 is fed into a gating pulse timer 76, in which the pulse 75 is modified to pulse 78 (FIG. 9). The pulse 78 opens gates of pulse conditioners 80 and 81, the former of which also receives a pulse 74' (FIG. 7) from the sensor 57. If during the existence of pulse 78, a change of illumination of sensor 57 occurs, pulses 83 and 84 (FIG. are emitted by the pulse conditioners 80 and 81. Thepulses 83 and 84 are modified by trigger pulse systems 86 and 87 to form trigger pulses 89 and 90. The trigger pulses 89 and 90 control power impulse systems 92 and 93, which discharge condensers 95 and 96 into the coil 30 in the casing 15.

From theforegoing circuit description, it will be obvious that thecondenser 95 is discharged into thecoil 30 when the sensor 57 is illuminated and condenser 96 is discharged. when the sensor 57 is occluded or blanked, but only when gating pulse 78 is available.

In mechanical terms, the operation of the apparatus will now-be described with referenceto FIG. 5.

The binding tape 63 is continuously sewn onto an upper component 65, and the resulting product is fed to the. cutting apparatus, i.e., onto theanvil 50. The sensors 56 and '57are occluded by the component 65, and, upon occlusion of the second sensor 57, the condenser 95 discharges to energize'the coil 30 which causes the cap 28 (i.e.-, core) to movedownwardly' with the plunger 23 and the blade 35 to cut-the tape 63 at the leading edge 69 of the component 65. The helical spring 32 immediately returns the cap 28, the plunger 23 and the blade 35 to the rest position (FIG. 1 Upon completion of the sewing of the tape 63 to the component 65, the trailing edge thereof uncovers first the sensor 56 and then the sensor 57 which results in transmission of another set of signals to the circuit causing the condenser 96 to discharge. Since the tape 63is fed continuously into the cutting apparatus withcomponents 65 continuously being attached thereto, the above cycle of operation is repeated for each component.

The time of chopping and the energy of impact of the blade are dependent on (1) the parameters of the solenoid defined by the cap 28, coil 30 and plunger 23, (2) the mass of magnet core defined by cap28 and the plunger 23, (3) the spring 32 and (4) the charge of condensers 95 and 96. Such parameters should be designed so'that the binding tape or strip 63 is cut in time shorter than 3 milliseconds and within a tolerance of, for example, 1:1/32inch.

It will be appreciated that the cutting apparatus can be used for cutting any strip of material, e.g., thread or tape, connected to a component and extending beyond at least one edge thereof. Of course, the component can be any textile or shoe component.

I claim:

v l. A cutting apparatus for cutting a strip of binding tape connected to a shoe upper component and extending beyond at least one edge thereof, the cutting being 7 performed at said one edge, said apparatus comprising a frame; a yoke on said frame; an arm slidably mounted in said yoke; a table portion on said frame for receiving said component and tape; a casing onone end of said arm opposite said yoke and above said table portion of the frame; plunger means housed in said casing and projecting therefrom toward said table portion of the frame; blade means on the outer end of said plunger for cutting said tape during passage of thecomponent and tape over said table portion of the frame; electromagnetic drive means for moving said plunger and blade means from arest position to a cutting position; sensor means for actuating said drive means when said component and said tape are properly located beneath said blade means; and means for returning said plunger I means and said blade means to said rest position, said electromagnetic drive means including a core formed of magnetic material mounted on said plunger means in said casing; a coil around said core; and circuit means for energizing said coil in response to signals from said sensor means, said sensor means including photoelectric cells positioned in the path of travel of said component in advance of said blade means,.and a light source for illuminating said photoelectric cells.

2. A cutting apparatus according to claim 1, includingan anvilremovably mounted in said table portion beneath said blade means; and a hard metal insert in said anvil for receivingsaid blade means during cutting of the tape.' A

3. A cutting apparatus according to claim 2, including a plate removably mounted on said frame adjacent said anvil, said sensor means including photoelectric cells in said plate means, said photoelectric cells being positioned in the path of travel of said components over said table portion in advance of said blade means, and a light source above said table portion for illuminating said photoelectric cells.

4. A cutting apparatus according to claim 3, wherein said'blade means is a flat blade pivotally mounted on the outer end of said plunger means and having a flat outer cutting edge extending transversely of said tape,

6 4 instantaneously discharging one or the other of said condenser means into said coil in response to signals from said photoelectric cells indicating that the component and tape are in position for cutting. 

1. A cutting apparatus for cutting a strip of binding tape connected to a shoe upper component and extending beyond at least one edge thereof, the cutting being performed at said one edge, said apparatus comprising a frame; a yoke on said frame; an arm slidably mounted in said yoke; a table portion on said frame for receiving said component and tape; a casing on one end of said arm opposite said yoke and above said table portion of the frame; plunger means housed in said casing and projecting therefrom toward said table portion of the frame; blade means on the outer end of said plunger for cutting said tape during passage of the component and tape over said table portion of the frame; electromagnetic drive means for moving said plunger and blade means from a rest position to a cutting position; sensor means for actuating said drive means when said component and said tape are properly located beneath said blade means; and means for returning said plunger means and said blade means to said rest position, said electromagnetic drive means including a core formed of magnetic material mounted on said plunger means in said casing; a coil around said core; and circuit means for energizing said coil in response to signals from said sensor means, said sensor means including photoelectric cells positioned in the path of travel of said component in advance of said blade means, and a light source for illuminating said photoelectric cells.
 2. A cutting apparatus according to claim 1, including an anvil removably mounted in said table portion beneath said blade means; and a hard metal insert in said anvil for receiving said blade means during cutting of the tape.
 3. A cutting apparatus according to claim 2, including a plate removably mounted on said frame adjacent said anvil, said sensor means including photoelectric cells in said plate means, said photoelectric cells being positioned in the path of travel of said components over said table portion in advance of said blade means, and a light source above said table portion for illuminating said photoelectric cells.
 4. A cutting apparatus according to claim 3, wherein said blade means is a flat blade pivotally mounted on the outer end of said plunger means and having a flat outer cutting edge extending transversely of said tape, whereby the blade is self-adjusting to ensure complete cutting action by the blade.
 5. A cutting apparatus according to claim 1, wherein said circuit means includes a pair of normally charged condenser means connected to said coil; and means for instantaneously discharging one or the other of said condenser means into said coil in response to signals from said photoelectric cells indicating that the component and tape are in position for cutting. 